1．Enough sleep is important to health．The amount of sleep needed（56）depends on the age of the person and the conditions in （57）which sleep takes place．The young may need more sleep than （58）the old，but usually eight hours are enough for the health of grown-ups．Some cando with （59）less than this amount，but others may need more．Every person knows his own need．（60）It is then a matter of good judgment to satisfy his need．Sleep （61）should always be enough to make one bring back his （62 ）strength （strong） and get ready for a day's work．
Fresh air is necessary to sound sleep．So it is not（63）without reason for some people to think that it is practicable to sleep in the open air．A bath at bedtime，（64）neither hot nor cool but of body temperature，may be helpful to sleep．Sleep-producing drug（幫助睡眠的藥物） should never be taken except when（65 ）suggested （suggest） by a doctor．
